US2850185A

US2850185A - Receptacle unloader

Info

Publication number: US2850185A
Application number: US623744A
Authority: US
Inventors: Willard E Erickson; Musschoot Albert
Original assignee: Link Belt Co
Current assignee: Link Belt Co
Priority date: 1956-11-21
Filing date: 1956-11-21
Publication date: 1958-09-02
Anticipated expiration: 1975-09-02

Description

Sept.,2, 1958 w. E. ERICKSON ET AL RECEPTACLE UNLOADER 5 Sheets-Sheet 1 Filed Nov. 21

Sept. 2, 1958 w. E. ERICKSON ET AL 2,350,185

RECEPTACLE UNLOADER Filed Nov; 21, 195e- V 5 Sheets-Sheet 2 Sept. '2, 1958 w. E. ERl'cKsoN ETAL RECEPTACLE UNLOADER 5 Sheets-Sheet 3 Filed Nov. 21, 1956 Sept. 2; 1958 w. E. ERICKSON ET AL 2,850,185

RECEPTACLE UNLOADER Filed' Nov. 21, 1956 s Sheets-Sheet 4 p 8 w. E. ERICKSON ET AL 2,850,185

RECEPTACLE UNLOADER 5 SheetsSheet 5 Filed Nov. 21, 1956 RECEPTACLE UNLQADER Willard Erickson, (Ihicago, and Albert Musschoot,

Park Ridge, lib, assignors to Link-Bait Company, a corporation of Illinois Application November 21, 1956, Serial No. 623,744

4 Claims. (Cl. 214-53) This invention relates to new and useful improvements in apparatus for causing material positioned in a receptacle on opposite sides of a given location to move in opposite directions toward said location, and deals more particularly with apparatus for oscillating a railway car in such a manner as to simultaneously discharge material from the opposite end portions of the car through its side door opening.

It has been found that material positioned in the opposite longitudinal portions of a railway car Will be moved in opposite directions toward a side door opening with a positive conveying action when the car is positioned on a base, the opposite end portions of which are supported for oscillation by oppositely inclined arms. When so supported, the floor of the car moves in a manner corresponding to that of the connecting rod of a four-bar linkage having nonparallel rocker arms of equal length. The oscillating movements of the base are limited so that an acute angle will always be maintained between each arm and the portion of the base between the arms.

Considering the movement of the base more specifically, it is a combined longitudinal reciprocation and tilting of the base alternately in opposite directions. In other words, as the base moves toward one end position of its longitudinal movement it is tilted in one direction and as it moves toward the opposite end position it is tilted in the opposite direction.

It is the primary object of this invention to provide apparatus for imparting movement to material positioned in the two half portions of a railway car, or other receptacle, in opposite directions relative to a location intermediate said portions, the apparatus being driven in such a mannerv as to impart identical conveying movements to the two portions of the car or receptacle.

A further important object of the invention is to provide apparatus for imparting combined reciprocatory and alternately oppositely directed tilting movements to a car or other receptacle, the motion imparting portion of-said apparatus being so designed as to minimize the starting load on the prime mover therefor When the apparatus is set into operation.

Still another object of the invention is to provide a drive. employing synchronously operated unbalanced shafts for applying forces to oscillate a railway car or other receptacle and to cause material in two relatively horiz ontally positioned portions thereof to move in opposite directions toward a location intermediate said portions.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like reference characters are employed to designate like parts throughout the same,

Figure 1 is a side elevational view of apparatus embodying the invention,

Figure 2 is a diagrammatic view illustrating a type of linkage that is incorporated in the structure illustrated in Fatented Sept- 2, 1958 ice Figure 3 is an enlarged vertical sectional view taken on line 3-3 of Fig. 1,

Figure 4 is an enlarged fragmentary end elevational lg 6W of the drive employed by the device illustrated in ig. 1, F Figure 5 is a top plan view of the drive illustrated in Figure 6 is a transverse vertical sectional view taken on line 6-6 of Fig. 4, and

Figure 7 is a longitudinal vertical sectional view taken on line 7-7 of Fig. 5.

In the drawings, wherein for the purpose of illustration is shown the preferred embodiment of the invention, and first particularly referring to Fig. 1, reference character 8 designates a box car that has been moved onto rails 9 carried by a movable base or platform 11. The box car 8 is centered on the base 11 between clamping devices 12 which are mounted for movement into engagement with the couplers 13 to restrain the car from movement on the base, as will be later described. It will be noted that one of the rails 9 is mounted on the base 11 at a greater elevation than the other rail so that the car 8 is supported in a laterally tilted position, as is best illustratedin Fig. 3.

The base 11 spans a shallow pit 14 and is supported for movement by arms 15 which are pivotally mounted in the bottom of the. pit 14 and extend upwardly and outwardly toward opposite end portions of the car 8 for pivotal connection to the base 11. The base 11 is urged or biased into its neutral position, at which the arms 15 lie at equal and opposite angles with the base, by spring assemblies 16 which are arranged to apply forces to the opposite end portions of the base in directions substantially normal to the arms 15.

At the opposite ends of the pit 14, jacks 17 are provided for engaging the bottom of the base 11 to support the latter against vertical movement during movement of the car 8 thereon.

Centered longitudinally of the base 11 is a drive 18 for imparting movement to the base 11. This drive is mounted on the underside of the base 11 and is actuated by a drive motor 19.

Referring now to Figs. 1 and 3 for a detail description of the arms 15 and the manner in which they support the base 11 in the pit 14, it will be seen that two spaced pairs of bearings 20 are mounted in transverse alignment on a weldment 21 beneath each end portion of the base 11 for pivotally supporting the shafts 22 at the lower ends of the arms. Each arm 15 is formed of two laterally spaced links 23 which are integral with a longitudinal web 24 and with a bushing 25 at each end portion of the arm. The bushing 25 at the lower end of each arm 15 is mounted on a portion of its associated shaft 22 which extends between and is supported for angular movement by the bearings 20. The two arms 15 associated with each of the wel'dments 21 extend upwardlyand outwardly toward the adjacent end of the base 11. The upper ends of these arms are connected to the base 11 by shafts 27 which extend through the bushings 25 at the upper ends of the arms and have their laterally extending end portions mounted for angular movement in spaced pairs of bearings 28 that are mounted on the bottom of the base 11.

It will be noted that each weldment 21 is provided with a standard 29, the top of which lies in closely spaced relation-ship with the bottom of the base 11 so that the latter may be supported thereon during installation, replacement :or repair of the arms 15 or spring assemblies 16.

As illustrated in Fig. 1, the jack 17 at each end of the pit 14 is formed of a toggle linkage 31 which is operated by a hydraulic motor 32 for vertical movement into and out of engagement with the bottom of the associated end portion of the base 11.

The clamping devices 12 are illustrated in their inoperative positions by broken lines in Fig. 1. When so positioned, the clamping devices lie within recesses 33 at the opposite ends of the pit 14 and are entirely below the level of the rails 9 so that cars 8 may be moved onto and off of the base 11 in any suitable manner. After a car 8 has been positioned on the base 11', however, the two clamping devices 12 are pivoted upwardly and moved longitudinally of the tracks 34 at opposite ends of the base 11 and into their operative positions by hydraulic cylinder type fluid motors 35. Each of the two fluid motors 35 is mounted to extend longitudinally of the base 11 and has its operating rod 36 pivotally connected to the associated clamping device 12 by a pin 37, as illustrated in Figs. 1 and 3.

It will be readily apparent that controlled, simultaneous operation of the two fluid motors 35 will permit centering of the car 8 on the base 11 between the clamping devices 12. Further, the continued application of fluid pressure to the motors 35 will maintain the devices 12 in tight clamping engagement with the couplings 13 to prevent any longitudinal movement of the car 8 on the base 11.

Referring now to Figs. 4 to 7, inclusive, for a detail description of the drive 18, it will be seen that it includes a pair of spaced parallel shafts 38 which extend transversely of and are rotatably supported on the bottoms of the opposite sides of the base 11 by bearings 39. As illustrated in Fig. 1, the two shafts 38 are centered longitudinally of the base 11 and are connected for synchronized rotation in opposite directions by the meshing gears 41 which are of the same diameter and have the same number of teeth. These gears are keyed to corresponding end portions of the shafts at one side of the base 11. Rotation of one of the gears will produce rotation of the other at the same speed but in an opposite direction as illustrated by the arrows of Fig 7. The two gears 41 are substantially completely enclosed by the housing 43 which is suspended on the side of the frame 11 by a bracket 44 at the top and by brackets 45 at opposite ends of the housing.

' At the opposite side of the base 11 from the housing 43, one of the shafts 38 has keyed thereon a drive sprocket 46 which is connected by a chain 47, or the like, to the sprocket 48 of the drive motor 19. Operation of the motor 19, therefore, will cause the sprocket 46 to rotate its associated shaft 38 and gear 41 which in turn will rotate the second gear 41 and its associated shaft 38 in the opposite direction.

Rigidly mounted in axially spaced relationship on each of the two shafts 38 are a pair of discs 49 which have mounted on the inwardly facing surfaces thereof a pair of arcuate retaining flanges 51. The flanges 51 associated with each pair of discs 49 are aligned axially of the shaft 38 upon which the discs are mounted, and a plurality of weights 52 extend between and are rigidly connected to the inner faces of the discs radially inwardly of the inner surfaces of the flanges 51. The weights 52, therefore, provide an eccentrically arranged or unbalanced counterweight for each of the two shafts 38. It will be noted, however, that the gears 41 connect the two shafts 38 in such a manner that the weights 52 are positioned above and below their respective shafts, as viewed in Fig. 7. In other words, when one set of weights 52 is positioned below its shaft, the other set of weights 52 will be positioned above its shaft. Rotation of the two shafts 38 in opposite directions, therefore, will position the weights 52 horizontally on corresponding sides of their associated shafts 38 so that the directions of eccentricity of the weights coincide in both directions longitudinally of the base.

Referring now to Figs. 1 and 2 for a detail description of the operation of the device, the car 8, loaded with grain or other flowable solid material, is moved onto the base 11 and approximately centered in any suitable manner. During this movement of the car 8, the clamping devices 12 will be in their inoperative positions in the recesses 33, as shown by broken lines in Fig. 1, and the jacks 17 will be in their elevated positions to support the base against vertical movement. The fluid motors 35 are thereafter actuated by the admission of pressure fluid thereto to cause the clamping devices 12 to move into engagement with the couplers 13 of the car 8 and to center the car on the base 11 where it will be restrained against further movement relative to the base. It will be noted at this point that the rails adjacent the ends of the pit 14 are arranged at the same difference of elevation as that of the rails 9 so that the car 8 will be laterally tilted as it moves onto the base 11 and will be righted as it is removed from the base.

After the car 8 has been properly positioned and clamped on the base 11, the fluid motors 32 are actuated to lower the jacks 17 so that the base 11 is supported for movement on the arms 15. The base is urged into a balanced or horizontal position, however, by the action of the spring assemblies 16 During or after the above described clamping and jack lowering operations, the door of the car 8 is opened so that a portion of the material adjacent the opening will spill into the material receiving hopper 53.

The drive motor 19 is then energized to rotate the two shafts 38 and the eccentrically positioned weights 52. It will be noted at this time that any initial movement of one shaft 38 which elevates its weights 52 is accompanied by a movement of the other shaft to lower its weights. In other words, the starting load on the drive motor 19 is maintained at a minimum by the counterbalancing effect of the weights 52 of each shaft on the weights of the other shaft. Because of the eccentric arrangement of the weights 52, oppositely rotating forces will be developed by the unbalanced action of the weights and these forces will be applied to the base 11 to effect movement of the latter. Any movement of the base 11, however, is opposed by the spring assemblies 16 to the extent that the forces exerted on the base by the spring assemblies at opposite ends thereof are unbalanced. In other words, movement of the base 11 in either direction from its neutral or balanced position is opposed by the spring assemblies 16 at one end of the base and assisted by those at the other end of the base and the difference between the spring forces is applied to the base in a direction tending to return the base to its balanced position. The inertia forces developed at the extremes of each oscillation of the base 11, car 8 and its contents at a given speed of rotation of the shafts 38 are substantially balanced by the difference between the spring forces. Thus, a relatively small total force developed by the eccentrically arranged weights 52 will produce oscillations of suflicient amplitude to cause the contents of the car 8 to be conveyed to and discharged through the center door opening.

Considering now the manner in which the rotating shafts 38 and their associated weights 52 develop and apply the oscillation producing forces to the base 11, it will first be noted that the directions of eccentricity of the weights 52 from theirassociated shafts are in agreement only in opposite horizontal directions. The forces developed by the rotating weights 52, therefore, are additive, and at a maximum value, only in the two opposite directions longitudinally of the base 11. This maximum force condition will be developed in both directions along the base during each revolution of the shafts 38. In other words, each revolution of the shafts 38 will produce one complete vibration or oscillation of the base. Of course, the opposite directions of rotation of the shafts will eliminate any dissimilarity in the oscillatory movements of the base 11 in opposite directions.

It might also be noted at this time that the directions of application of the forces to the base 11 by the shafts 38 relative to the directions of eccentricity of the Weights 52 on their shafts will depend upon the speed of rotation of the shafts. More specifically, when the shafts 38 are rotated at speeds below the natural vibration frequency of the system comprised of base 11 and spring 16 the forces applied to the base 11 will agree in direction with the directions of eccentricity of the weights 52 from their associated shafts. At speeds above the natural vibration frequency of the above mentioned sys tem, however, each shaft 38 and its associated weights 52 will tend to rotate about a spin axis passing through their combined center of gravity so that the forces applied to the base 11 by the shaft will be in a direction opposite the direction of eccentricity of the weights from their associated shaft. In either event, however, the speed of rotation of the shafts 38 will equal the operating frequency or the frequency of forced vibration of the base 11.

The car 8 being supported by and held in a relatively fixed position on the base 11 will move with the base and the material within the car will also, to some extent, move with the car and base. The material, car 8 and base 11, therefore, form a resiliently supported body having a natural vibration frequency which will vary in accordance with the weight of the material in the car. Movement of the material within the car 8 will have a dampening effect upon the free vibration of the material, car and base 11, however, so as to limit the amplitude of vibration during temporary operation at the natural frequency. Ordinarily, however, the speed of notation of the shafts 38 is brought up immediately after starting to an operating frequency which exceeds the natural frequency of the material, car 8 and base 11. During the acceleration of the operating frequency through the natural frequency, a short period of resonant frequency operation will occur but due to the previously mentioned dampening effect of the material, this short period of resonant frequency operation will have no harmful effects.

The vibrations or oscillations imparted to the base 11 and the car 8 thereon by the shafts 38 and their associated weights 52 will impart a positive conveying action to the material in the opposite end portions of the car to move the material from both end portions toward the door of the car. Additionally, the tilted position of the car will cause the material to flow toward the lower side thereof so that the material will spill from the door opening into the material receiving hopper 53.

This conveying action of the car body, and primarily its floor, upon the material in the opposite end portions of the car 8 can best be explained by reference to Fig. 2, in which the connecting rod 11a, the fixed link 14a and the rocker arms 15:; correspond to the base 11, the floor of the pit 14 and the supporting arms 15 of the structure illustrated in Fig. l. The arms 15a are of equal length and are arranged in nonparallel relationship while the length of the connecting rod 11a is greater than the distance between the pivotal connections of the arms 15a and the fixed link 14a. Similarly, the portion of the base 11 between its pivotal connections to the upper ends of the arms 15 is greater than the spacing between the pivotal mountings of the arms on the bottom of the pit 14. It will be appreciated that the extent of movement of the connecting rod 11a between its extreme positions A and B has been exaggerated to more clearly illustrate the principle of operation of the device.

As illustrated in Fig. 2, the point of pivotal connection between each of the rocker arms 15a and the connecting rod 11a moves upwardly and inwardly along an inclined arcuate path as the point of pivotal connection between the other arm and the connecting rod moves downwardly along an oppositely inclined arcuate path when the arms are oscillated relative to the fixed link 14a. Of course, the directions of movement of the points of pivotal connection are reversed during successive strokes of each oscillation. As the connecting rod moves in either direction away from, and is subsequently returned to, its position C of equal angularity with the rocker arms 15a, it is tilted downwardly in the direction of its movement and returned to its horizontal position, respectively. It will be readily apparent that movements of the base 11 must correspond with those of the connecting rod 11a and that the movements of the floor of the car 8 will substantially conform to those of the base 11.

Considering first the movements of the right hand end portion of the car 8, as viewed in Fig. 1, and the movements of this end portion of the car floor from the position A of the connecting rod 11a to the position B of the connecting rod, it will be seen by reference to Fig. 2 that the material supported by the floor, and to a limited extent by the lower tilted side wall of this portion of the car, will move with the car and will be given a component of movement which is inclined upwardly and longitudinally inwardly from its initial position toward a fixed location near the middle of the car. When, however, the direction of movement of the car floor is reversed for its return to position A, the trajectory of the mass of material in this end portion of the car 8 will cause it to continue its movement longitudinally inwardly from its initial position but relative to the car and to fall back into supported relation relative to the car floor at a point nearer the door than that from which it was initially projected. At approximately the same time that the material has returned into supported relation relative to the car floor, it will again be subjected to the conveying acti-on described above. In other words, alternate movements of this end portion of the car 8 from position A to position B and from position B back to position A will cause the material to be moved first with the car and then relative to the car but substantially continuously toward a fixed location near the middle of the car.

As clearly illustrated in Fig. 2, the opposite end portion of the car 8 will be moved in the same manner as the first described end portion but in an oppositely inclined direction and with a phase diiference of one hundred and eighty degrees so that the material therein will be subjected to an identical but oppositely directed con-- veying action during alternate strokes of operation. Since the material in both end portions of the car 8 moves substantially continuously and in opposite directions relative to a fixed location near the middle of the car, there appears to be simultaneous movement of the material in the two end portions toward the car door. Of course, the flowable nature of the material being unloaded will prevent the entire mass of the material from moving by increments away from the opposite ends of the car 8. The positive conveying action imparted to the car 8, however, will cause the material to flow out of the open door quickly and will effect a complete removal of the material from the car. The tilted condition of the car 8 facilitates the discharge of the material through the door opening.

It is to be understood that the form of this invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, we claim:

1. A device for moving material in opposite end portions of a railway car in opposite directions toward the middle portion of the car for discharge through a contrally located side wall opening, comprising an elongated base having rails mounted thereon for receiving a railway car, means for retaining said car at a central position upon said base for movement with said base, means supporting said base for alternately oppositely directed plane motion having translational and rotational components such that the base is movable alternately in opposite longitudinal directions and during successive longitudinal movements is pivoted in opposite directions about its transverse center line, and means for oscillating said base upon said supporting means comprising a pair of unbalanced shafts mounted on said base for rotation about parallel axes spaced longitudinally of said base and extending transversely thereof, and means for rotating said shafts in opposite directions and at synchronized speeds with the directions of unbalance of the shafts coinciding in both directions longitudinally of said base.

2. A device for moving material in opposite end portions of a railway car in opposite directions toward the middle portion of the car for discharge through a centrally located side wall opening, comprising an elongated base having rails mounted thereon for receiving a railway car, means for retaining said car at a central position upon said base for movement with said base, means supporting said base for alternately oppositely directed plane motion having translational and rotational components such that the base is movable alternately in opposite longitudinal directions and during successive longitudinal movements is pivoted in opposite directions about its transverse center line, and means for oscillating said base upon said supporting means comprising a pair of unbalanced shafts mounted on said base for rotation about parallel axes spaced longitudinally of said base and extending transversely thereof, means drivingly connecting said shafts for synchronized rotations in opposite directions with the directions of unbalance of the shafts in phase in both directions longitudinally of said base, and a prime mover mounted on said base for jointly rotating said shafts, whereby the unbalanced condition of the rotating shafts causes said shafts to apply alternately oppositely directed longitudinal forces to said base.

3. A device for moving material in opposite end portions of a railway car in opposite directions toward the middle portion of the car for discharge through a centrally located side wall opening, comprising an elongated base having rails mounted thereon for receiving a railway car, means for retaining said car at a central position upon said base for movement with said base, means supporting said base for alternately oppositely directed plane motion having translational and rotational components such that said base is movable alternately in opposite longitudinal directions and during successive longitudinal movements is pivoted in opposite directions about its transverse center line, and means for oscillating said base upon said supporting means comprising a pair of parallel shafts spaced longitudinally and extending transversely of said base for rotation relative thereto about axes symmetrically disposed on either side of the transverse center line of said base, means drivingly connecting said shafts for synchronized rotation in opposite directions, a weight eccentrically mounted on each of said shafts, said Weights being equal and their directions of eccentricity coinciding longitudinally of said base, and drive means mounted on said base for rotating said shafts.

4. A device for moving material in opposite end portions of a railway car in opposite directions toward the middle portion of the car for discharge through a centrally located side wall opening, comprising an elongated base having rails mounted thereon for receiving a railway car, means for retaining said car at a central position upon said base for movement with said base, means supporting said base for alternately oppositely directed plane motion having translational and rotational components such that the base is movable alternately in opposite longitudinal directions and during successive longitudinal movements is pivoted in opposite directions about its transverse center line, and means for oscillating said base upon its supporting means comprising a pair of unbalanced shafts rotatably mounted on said base for rotation about axes symmetrically disposed upon either side of the transverse center line of said base and aligned with the translational component of motion of said base, a pair of gears having equal diameters rigidly mounted on said shafts in meshed relationship with each other for synchronized rotation in opposite directions with the directions of unbalance of said shafts coinciding in both directions of alignment with the translational component of movement of said base, and a motor mounted upon said base and drivingly connected to one of said shafts for rotating said shafts.

References Cited in the file of this patent UNITED STATES PATENTS 2,200,724 Robins May 14, 1940 2,266,594 Ertel Dec. 16, 1941